The Exxon Valdez oil spill occurred in Prince William Sound, Alaska, on
Good Friday, March 24, 1989, when Exxon
Valdez, an oil
tanker bound
for Long Beach, California, struck Prince William Sound's Bligh
Reef at 12:04 am local time and spilled 11 to 38 million US
gallons (260,000 to 900,000 bbl; 42,000 to 144,000 m3) of crude
oil over the next few days. It is considered to
be one of the most devastating human-caused environmental
disasters. The Valdez spill was the largest in US waters
until the 2010 Deep water Horizon oil
spill, in terms of volume released. However, Prince William
Sound's remote location, accessible only by helicopter, plane, or boat, made
government and industry response efforts difficult and severely taxed existing
plans for response. The region is a habitat for salmon, sea
otters, seals and seabirds. The
oil, originally extracted at the Prudhoe Bay oil field,
eventually covered 1,300 miles (2,100 km) of coastline, and 11,000 square
miles (28,000 km2) of ocean.
According
to official reports, the ship was carrying approximately 55 million US
gallons (210,000 m3) of oil, of which about 10.1 to
11 million US gallons (240,000 to 260,000 bbl; 38,000 to
42,000 m3) were spilled into the Prince William Sound. A figure
of 11 million US gallons (260,000 bbl; 42,000 m3) was
a commonly accepted estimate of the spill's volume and has been used by the
State of Alaska's Exxon Valdez Oil Spill Trustee Council, the National Oceanic and
Atmospheric Administration and
environmental groups such as Greenpeace and the Sierra
Club. Some
groups, such as Defenders of Wildlife,
dispute the official estimates, maintaining that the volume of the spill, which
was calculated by subtracting the volume of material removed from the vessel's
tanks after the spill from the volume of the original cargo, has been
underreported. Alternative calculations, based on the assumption that the
official reports underestimated how much seawater had been forced into the
damaged tanks, placed the total at 25 to 32 million US gallons (600,000 to
760,000 bbl; 95,000 to 121,000 m3).
Identified causes
Multiple factors have been
identified as contributing to the incident:
·
Exxon Shipping Company failed to supervise
the master and provide a rested
and sufficient crew for Exxon Valdez. The NTSB found this was
widespread throughout the industry, prompting a safety recommendation to Exxon
and to the industry.
·
The
third mate failed to properly maneuver the vessel, possibly due to fatigue or
excessive workload.
·
Exxon Shipping Company failed to properly
maintain the Raytheon Collision Avoidance
System (RAYCAS) radar, which, if functional,
would have indicated to the third mate an impending collision with the Bligh Reef by detecting the "radar
reflector", placed on the next rock inland from Bligh Reef for the purpose
of keeping ships on course. This cause has only been identified by Greg Palast (without evidentiary support) and is
not present in the official accident report.
Captain Joseph Hazelwood, who was widely reported to have been
drinking heavily that night, was not at the controls when the ship struck the
reef. However, as the senior officer, he was in command of the ship even though
he was asleep in his bunk. In light of the other findings, investigative
reporter Greg Palast stated in 2008, "Forget the drunken skipper fable. As
to Captain Joe Hazelwood, he was below decks, sleeping off his bender. At the
helm, the third mate never would have collided with Bligh Reef had he looked at
his RAYCAS radar. But the radar was not turned on. In fact, the tanker's radar
was left broken and disabled for more than a year before the disaster, and
Exxon management knew it. It was [in Exxon's view] just too expensive to fix
and operate." Exxon blamed Captain Hazelwood for the grounding of
the tanker.
Other
factors, according to an MIT course entitled
"Software System Safety" by Professor Nancy G.
Leveson, included:
1. Ships were not informed
that the previous practice of the Coast Guard tracking ships out to Bligh Reef
had ceased.
2. The oil industry promised,
but never installed, state-of-the-art iceberg monitoring equipment.
3. Exxon Valdez was sailing outside
the normal sea lane to avoid small icebergs thought to be in the area.
4. The 1989 tanker crew was
half the size of the 1977 crew, worked 12- to 14-hour shifts, plus overtime.
The crew was rushing to leave Valdez with a load of oil.
5. Coast Guard vessel
inspections in Valdez were not performed, and the number of staff was reduced.
6. Lack of available equipment
and personnel hampered the spill cleanup.
This
disaster resulted in International Maritime Organization introducing
comprehensive marine pollution prevention rules (MARPOL) through various conventions. The rules were ratified by
member countries and, under International Ship Management rules, the ships are
being operated with a common objective of "safer ships and cleaner
oceans".
In
2009, Exxon Valdez Captain Joseph Hazelwood offered a
"heartfelt apology" to the people of Alaska, suggesting he had been
wrongly blamed for the disaster: "The true story is out there for anybody
who wants to look at the facts, but that's not the sexy story and that's not
the easy story," he said. Yet Hazelwood said he felt Alaskans always gave
him a fair shake.
Economic and
personal impact
In
1991, following the collapse of the local marine population (particularly
clams, herring and seals) the Chugach Alaska Corporation, an Alaska Native Corporation,
filed for Chapter 11 bankruptcy protection. It
has since recovered.
According
to several studies funded by the state of Alaska, the spill had both short-term
and long-term economic effects. These included the loss ofrecreational sports,
fisheries, reduced tourism, and an estimate of what economists call "existence
value", which is the value to the public of a pristine
Prince William Sound.
The
economy of the city of Cordova,
Alaska was adversely affected after the spill damaged stocks of salmon and herring in the area.
In
2010, a CNN report alleged that many oil spill cleanup workers involved in the
Exxon Valdez response had subsequently become sick. Anchorage lawyer Dennis
Mestas found that this was true of 6,722 of 11,000 worker files he was able to
inspect. Access to the records was controlled by Exxon. Exxon responded in a
statement to CNN:
"After
20 years, there is no evidence suggesting that either cleanup workers or the
residents of the communities affected by the Valdez spill have had any adverse
health effects as a result of the spill or its cleanup."
References:
https://en.wikipedia.org/wiki/Prince_William_Sound
https://en.wikipedia.org/wiki/Chugach_Alaska_Corporation
https://en.wikipedia.org/wiki/Salmon
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